The study also found that another genetic variant might play a role in the lower risk of colorectal cancer associated with eating vegetables, fruits and fiber.

The findings could have public health significance since diet is a modifiable risk factor for this type of cancer, the researchers said.

The study included more than 9,000 people with colorectal cancer and a similar-sized group of people without cancer. The investigators said they found a significant interaction between the genetic variant known as rs4143094 and processed meat consumption. This variant is located in a chromosome region that includes GATA3, a gene previously linked to several forms of cancer.

Another significant diet-gene link was found in the genetic variant rs1269486, which was associated with a reduced risk of colorectal cancer, according to the study. It is scheduled for presentation Thursday at the annual meeting of the American Society of Human Genetics, in Boston.

How specific foods affect genes and colorectal cancer risk is unknown, but the digestion of processed meat may cause inflammation or immune system responses that might trigger tumor development, the researchers said.

"It is conceivable that selected individuals at higher risk of colorectal cancer based on genomic profiling could be targeted for screening, diet modification and other prevention strategies," study coauthor Jane Figueiredo, an assistant professor of preventive medicine at the University of Southern California, said in a society news release.

This study was presented at a medical meeting, so the findings should be viewed as preliminary until published in a peer-reviewed journal.